Analog Devices Inc./Maxim Integrated MXD1813XR44+

Overview

MXD1813XR44+ from Maxim Integrated is a low-power, open-drain, active-low microprocessor reset supervisor IC for +5V systems, featuring a factory-set 4.37V reset threshold (±2.5% over temperature), 100ms minimum reset timeout, and debounced manual-reset detection with 1.5μs minimum push-button assertion time. It operates from -40°C to +105°C in SC70-3 package and is used to ensure reliable power-up sequencing and brownout recovery in embedded controllers.

For engineers reviewing the MXD1813XR44+ datasheet, MXD1813XR44+ pinout, MXD1813XR44+ application, or MXD1813XR44+ equivalent, key selection criteria include its 4.37V V_TH, open-drain RESET output with internal 5.5kΩ pullup, manual-reset debounce capability, guaranteed operation down to V_CC = +1V, and immunity to sub-10μs V_CC transients.

Technical Context

The MXD1813XR44+ implements a precision bandgap-based voltage comparator monitoring V_CC against a trimmed 4.37V threshold, with hysteresis and transient rejection circuitry that suppresses glitches under 10μs duration at typical overdrive levels. Its internal timer guarantees ≥100ms reset assertion after V_CC recovery or manual reset release.

As an open-drain active-low supervisor with integrated 5.5kΩ pullup resistor and dedicated manual-reset input (RESET pin), it supports bidirectional μP reset interfaces and mechanical switch debouncing without external components-enabling clean, glitch-free reset initiation in space-constrained portable designs.

Key Specifications

Pinout & Package

MXD1813XR44+ is housed in a 3-pin SC70 package (outline X3-2), measuring 2.0mm × 1.25mm × 0.9mm, suitable for high-density PCB layouts and portable applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor reset supervision applications.

Compared with MXD1813XR44+, MAX809TR44+T offers identical threshold accuracy but lacks manual-reset functionality and requires external biasing for bidirectional interfaces, while TPS3808G33DBVR targets different voltage domains and adds configurability at the cost of higher current and non-equivalent threshold.

Availability

MXD1813XR44+ is available at Aetrix Electronics and suitable for computers and controllers, intelligent instruments, set-top boxes, and printers requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MXD1813XR44+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for industrial, computing, and communications applications.

The MXD1810–MXD1813/MXD1815–MXD1818 product line delivers ultra-low-power, factory-trimmed reset supervisors targeting space-constrained, battery-sensitive, and high-reliability embedded systems operating from -40°C to +105°C.

FAQ

What is the reset threshold voltage of the MXD1813XR44+?

The MXD1813XR44+ has a factory-set reset threshold of 4.37V, with ±2.5% accuracy over the full operating temperature range (-40°C to +105°C). This value is specified in the Electrical Characteristics table under "Reset Threshold (V_TH)" for suffix R44, and is optimized for reliable monitoring of +5V power supplies in industrial and consumer electronics. The MXD1813XR44+ uses this precise threshold to assert reset during brownout conditions before system instability occurs.

Does the MXD1813XR44+ support manual reset via an external pushbutton?

Yes, the MXD1813XR44+ features a debounced manual-reset input on its RESET pin, requiring only a >1.5μs low pulse to initiate a guaranteed 100ms reset timeout period. This function is explicitly enabled in the MXD1813 and MXD1818 variants per the datasheet's "Push-Button Reset" section and functional diagram. The MXD1813XR44+ integrates internal debouncing circuitry, eliminating the need for external RC filters when interfacing with mechanical switches.

What package type and footprint does the MXD1813XR44+ use?

The MXD1813XR44+ is supplied in a 3-pin SC70 package (outline X3-2), with dimensions of 2.0mm × 1.25mm × 0.9mm and a standard 0.65mm pin pitch. Its top marking is "AIA", as confirmed in Table 1 of the datasheet. This compact footprint is ideal for portable and high-density applications, and the device is RoHS-compliant with lead-free termination indicated by the "+" suffix in the part number MXD1813XR44+.

Is the RESET output of the MXD1813XR44+ push-pull or open-drain?

The RESET output of the MXD1813XR44+ is open-drain and active-low, with an internal 5.5kΩ pullup resistor to V_CC. This configuration is confirmed in the Pin Descriptions section for MXD1813/MXD1818 and distinguishes it from push-pull variants like MXD1812. The MXD1813XR44+'s open-drain output enables direct interfacing with bidirectional microprocessor reset pins (e.g., Motorola 68HC11) without requiring an external pullup resistor.

What is the minimum supply voltage at which the MXD1813XR44+ guarantees valid RESET output?

The MXD1813XR44+ guarantees valid RESET/RESET output down to V_CC = +1.0V, as stated in the General Description and Absolute Maximum Ratings sections. This specification ensures deterministic reset behavior during deep brownout conditions, preventing undefined states in connected microprocessors. Unlike some competitors, the MXD1813XR44+ maintains logic-level integrity well below nominal operating voltage, a critical feature for fail-safe system design.